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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-ia64/semaphore.h | |
download | blackbird-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz blackbird-op-linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-ia64/semaphore.h')
-rw-r--r-- | include/asm-ia64/semaphore.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/include/asm-ia64/semaphore.h b/include/asm-ia64/semaphore.h new file mode 100644 index 000000000000..3a2f0f3f78f3 --- /dev/null +++ b/include/asm-ia64/semaphore.h @@ -0,0 +1,102 @@ +#ifndef _ASM_IA64_SEMAPHORE_H +#define _ASM_IA64_SEMAPHORE_H + +/* + * Copyright (C) 1998-2000 Hewlett-Packard Co + * Copyright (C) 1998-2000 David Mosberger-Tang <davidm@hpl.hp.com> + */ + +#include <linux/wait.h> +#include <linux/rwsem.h> + +#include <asm/atomic.h> + +struct semaphore { + atomic_t count; + int sleepers; + wait_queue_head_t wait; +}; + +#define __SEMAPHORE_INITIALIZER(name, n) \ +{ \ + .count = ATOMIC_INIT(n), \ + .sleepers = 0, \ + .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ +} + +#define __MUTEX_INITIALIZER(name) __SEMAPHORE_INITIALIZER(name,1) + +#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ + struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) + +#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) +#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name, 0) + +static inline void +sema_init (struct semaphore *sem, int val) +{ + *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); +} + +static inline void +init_MUTEX (struct semaphore *sem) +{ + sema_init(sem, 1); +} + +static inline void +init_MUTEX_LOCKED (struct semaphore *sem) +{ + sema_init(sem, 0); +} + +extern void __down (struct semaphore * sem); +extern int __down_interruptible (struct semaphore * sem); +extern int __down_trylock (struct semaphore * sem); +extern void __up (struct semaphore * sem); + +/* + * Atomically decrement the semaphore's count. If it goes negative, + * block the calling thread in the TASK_UNINTERRUPTIBLE state. + */ +static inline void +down (struct semaphore *sem) +{ + might_sleep(); + if (atomic_dec_return(&sem->count) < 0) + __down(sem); +} + +/* + * Atomically decrement the semaphore's count. If it goes negative, + * block the calling thread in the TASK_INTERRUPTIBLE state. + */ +static inline int +down_interruptible (struct semaphore * sem) +{ + int ret = 0; + + might_sleep(); + if (atomic_dec_return(&sem->count) < 0) + ret = __down_interruptible(sem); + return ret; +} + +static inline int +down_trylock (struct semaphore *sem) +{ + int ret = 0; + + if (atomic_dec_return(&sem->count) < 0) + ret = __down_trylock(sem); + return ret; +} + +static inline void +up (struct semaphore * sem) +{ + if (atomic_inc_return(&sem->count) <= 0) + __up(sem); +} + +#endif /* _ASM_IA64_SEMAPHORE_H */ |